Painted ceilings or, the fifth wall

After my post on painted porch ceilings, now I am on a painted ceiling kick. On Oprah the other day, her designer, Nate Berkus, presented a series of home makeovers. And what do you know, one has a painted ceiling!
Nate painted the ceiling a vibrant green. "People are like, 'Oh my ceiling has to be white'—it really doesn't," he says. (image and quote source)
Here's a lovely, subtle one from Domino magazine
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Of course, you can get super fancy, and take ceiling colors to the next level, like this:
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I like how the designer took a utilitarian space that usually is just ignored, and tied it into the interior space, creating a dynamic sense of flow and continuity. So much more interesting than plain concrete, don't you think?

Or this... (and yes, this is just painted to -look- like a window and sky)
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When I am doing a residential color consultation for a client with unusually low ceilings, such as those in basements, I often recommend that they paint their ceiling the same color as the walls. That way, your eye is not drawn up to the ceiling where the contrast is greatest, between walls and ceiling. It blends it out, almost becoming a continuation of the walls.

If you were to go for a colored ceiling, what hue would it be? Anyone actually paint his or her ceilings something other than white?